It is an EPA-tractor, which is apparently a particular Swedish cathegory. Started during the 30ies but really took off during the war.

Tractor - Wikipedia, the free encyclopedia

During World War II, a shortage of tractors in Sweden led to the development of the so-called "EPA" tractor (EPA was a chain of discount stores and it was often used to signify something lacking in quality). An EPA tractor was simply an automobile, truck or lorry, with the passenger space cut off behind the front seats, equipped with two gearboxes in a row. When done to an older car with a ladder frame, the result was not dissimilar to a tractor and could be used as one.

After the war it remained popular, now not as a farm vehicle, but as a way for young people without a driver's license to own something similar to a car. Since it was legally seen as a tractor, it could be driven from 16 years of age and only required a tractor license. Eventually, the legal loophole was closed and no new EPA tractors were allowed to be made, but the remaining ones were still legal, which led to inflated prices and many protests from people who preferred EPA tractors to ordinary cars.

IIRC, wood gas was once also used in some places instead of coal gas (way before coal gas was replaced by natural gas as the gas of preference).

My grandfather had quite a few stories about his experiences with wood gas (he drove deliveries during the war). Often involved getting stuck at a steep hill.

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